Telephone system.



No. 716,802., Patehted Dec. 23, 1902.

W. C. WRIGHT.

TELEPHONE SYSTEM.

{Application Med Jan. 2. 1.902.;

(No Model.)

W (TA 5, 5 5

UNITED STATES PATENT OrFicE.'

TWAYN E 0. WVRIGHT, OF AMARILLO, TEXAS.

TELEiH-ON E SYSTEM.

SPECIFICATION forming part of Letters Patent No. 716,802, dated December23, 1902.

A nmmm January 29, 1902.

To ctZZ whom, it minty concern;

Be it known that I, WAYNE G. WRIGHT, a citizen of the United States,residing at Amarillo, in the county of Potter, State of Texas, haveinvented certain new and useful Improvements in Telephone Systems; and Ido hereby declare the following to be a full, clear, and exactdescription ofv the invention, such as willenable others skilled in theart to which it appertains to make and use the same.

This invention relates to automatic switchboards; and it has for itsobject to provide a construction of board and a connected system ofwiring which will permit a subscriber at a telephone in one town to callup the operator or central at a distant point and converse with himwithout operating the other instruments in his town and at the same timepreventing other subscribers from breaking into the line.

A further object of the invention is to provide for permitting theoperator to connect a subscriber in one town with a subscriber inanother town in such manner that other subscribers cannot break into theline, this connecting of the subscribers being done from a distantpoint. i

A further object of the invention is to per-' mit of a subscriber in onetown talking on the main line through the next town and to a third townwithout permitting the subscriber in the intermediate town to come intothe line or hear the conversation.

Other objects and advantages of the invention will be understood fromthe following description and include-the provision of means forpermitting the different subscribers in the same town to talk amongthemselves independently of other subscribers.

In the drawings forming a portion of this specification, and in whichlike numerals of reference indicate similar parts of the several views,Figure 1 is a diagrammatic view showing two of the switchboardsconnected in series in a main line with central. Fig. 2 is a rearelevation of the dial-plate, showing the means for progressing thecircuit-closing hand of the switchboard with a step-by-step movement.Fig. 3 is a View showing one of the receiver hooks or levers.

Referring now to the drawings, there are shown in the present instancetwo switchserial No. 91,713. (No model.)

boards Aand a,one of which is located at each town to be placed incommunication, and with the switchboard A areconnected the two sub- Theswitchboard A consists of a dial B, of insulating material, on which ismounted, adjacent to the edge thereof, an annular series of twenty-fourcontact-points,as shown. Four of the contact-points D, E, F, and G areelectrically connected mutually and may be known as the signal-contacts,inasmuch as the signal-line H, hereinafter more particularly referredto, is connected thereto. This sign al-line extends to all of thesubscribers instruments that are connected with the switchboard A. g

The four contacts D, E, F, and G are spaced equally about the peripheryof the dial, and between each pair of these signal-contacts are fiveother contacts, as shown. The switchboard or also has foursignal-contacts d, e, f, and g, all of which are electrically connectedwith the signal wire or line h,which leads to the subscribers instrumentcand which signal or line wire is connected normally, as here--inafterdescribed,with instrument 0" through the wire 71, the plate 47on the lever 39, and the contacts with which said plate normally engage.

To the right of the contact D, rotatably of the dial, is a contact 1, towhich is connected the subscribers line I, while on the switchboard a,next to the contact cl, is a dead-contact l. The line I leads to thesubscribers station 0. The second contact onthe board A (shown at 5) isconnected with the contact I referred to, the third contact 6 is adeadcontact, and the fourth and fifth contacts 2 and a are connectedwith the contact numbered 1. The contact 5 and the contact 6 on theboard a correspond to the contacts 5 and 6 in location and aredead-contacts, while the contact 2, corresponding to contact 2 on boardA, is connected with the contact 2*, which is the first contact to theright of the contact e and corresponds in location to the contact 2 onthe board A. Next to the contact 2 is a dead-contact 7, corresponding tocontact 7 on board a, and each contact 7 is in circuit with 2. The thirdcontact from contacts E and e, respectively, (shown at 8 and 8) aredead-contacts. On board A contact 1, next to the contact 8, is connectedwith the contact 1, while the corresponding contact 1 on the board a isconnected with the contact 7 and the contact 3, which is adjacent to thecontact 1. The contact 3 on the board A, adjacent to the contact F andcorresponding to the contact 3 of the board a, is connected with asubscribers contact 3, connected by wire K with the subscribersinstrument 0. The contact 2 on the board a is likewise a subscriberscontact and is connected by wire 70 with the subscribers instrument c".The subscribers contact 3 on the board A is to the right of thesignal-contact F and corresponds to the contact 3 to the right of thecontact fou the board a. The contact 9 on board A is connected withcontact 3, as are also contacts 2 and 4 corresponding to contacts 2 and4 on the board a. The contact 10 on board A between contacts 9 and 2 isa dead-contact. On the board a the contacts 9 and 10, corresponding tocontacts 9 and 10, are dead-contacts, while the contact 2 is connectedwith contact 2 and the contact 4" is connected with 4. Next to thecontact G are three deadcontacts 4, 11, and 12, while on the board a,next to the contact g, are the contacts 4", 11, and 12, of which contact11 is connected with a subscribers contact 4*, while the contact 12 isdead. A wiret' connects the contact 4 with the subscriber c. On theboard A, next to the contact 12, is a contact 1, which is connected withthe contacts 1 and 1 while between the contacts 1 and D is a contact 3,which is connected with contacts 3 and 3 It will thus be seen that onthe board A all of the contacts 1, 1, and 1 are electrically connected,as also the contacts 3, 3*, and 3 these being the main contacts for thesubscribers O and C". On the board a, the contacts 2, 2*, and 2 areconnected, while contacts 4, 4, and 4 are connected.

At the center of each dial is a shaft 15 and 15, respectively, the twoshafts carrying hands 16 and 16, having circuit-closing brushes orcontact-fingers at their free ends, which engage the contactssuccessively as the hands are rotated over the faces of their respectivedials. Each of the shafts referred to is provided with anescapement-wheel 17, with which is engaged an escapement-lever 18,carrying a polarized armature 19 in the field of force of anelectromagnet 20, so that when the magnet is energized by an alternatingcurrent the escapement-lever will be vibrated to permit rotation of theshaft 15 under the influence of the weight 21, suspended from the cord22 wound upon the shaft. The electromagnets are connected between thehands and the ground, while connecting the hands of the two instrumentsis a line-wire 23. From the hand 16 leads a main line-wire 24 to theoperators station 25 or central, while from the hand 16 leads a mainline-wire 26, which may extend to a third switchboard or any otherinstrument at a distant station. At station 0 is a transmitter 30, oneterminal of which is connected through the primary coil 31 of aninductioncoil and through a local battery 32 to the ground. The secondterminal of the transmitter is connected by a wire 37 with thecontact-point 38, which is engaged by the lever or receiver-hook 39 whenthe receiver is in use, said lever 39 having the wire K connectedthereto. A receiver 40 is connected with the secondary winding 41 of theinduction-coil, so that when the receiveris off of the hook and thelever 39 is in engagement with the contact 38 conversation may be heldover the wire K. Upon the lever 39 is an insulating-block 46, on whichis a contact-plate 47 for engagement with the two contact-points 48 and49 when the receiver is on the hook, the wire I-I being broken andhaving its ends connected to the points, as shown, so that when thereceiver is from the hook the circuit of the wire H between theinstruments 0 and C is broken. From the contact 48 the wire H extends tothe spring-finger at the subscribers instrument 0, a branch wire H beingconnected with a switch-point 50, which is disposed for engagement by ahooklever 51, connected with the wire 1.

At central is a source M of alternating cur rents, which are passed overthe main line and which energize the two magnets simultaneously, so thatthe hands 16 and 16' traverse the dials in unison to engagecorresponding points of the dials.

Below the hook-lever 39 and in position for engagement thereby when thereceiver is removed therefrom is a contact 52, which is connected withthat portion of the wire H connected to the contact 49.

At the subscribers station 0' is a transmitter 53, connected through theprimary winding 54 of an induction-coil and battery with the ground,said transmitter being also connected with the contact 55, which isengaged by the lever 51 when the receiver is removed therefrom. At thesame time the lever 51 engages the contact 50, and as the wire I isconnected with the lever 51 said wires H and I are connected in multiplewith the transmitter 53. In the path of the movement of the lever 51,under the influence of the weight of the receiver, is a contact 56,connected with the magneto 57 and connected also through the bell 58with the ground.

Supposing that subscriber O wishes to talk with C", it being understoodthat the hand 16 is normally on one of the signal-contacts D, E, F, orG, the subscriber operates the magneto 57 and the current passing overthe line H and through the contact-strip 47 to the point F passes thenceto the hand 16 and to the operator who is rung up. The subscriber C thenremoves his receiver from his hook 51, which latter engages the contact50, and

places his transmitter in circuit with the signal line or wire H. Hethen converses over the signal wire and tells the operator that hewishes to talk to the subscriber at C. The operator then moves the hand16 to 3 and rings up 0 over his wire K. Subscriber at G" removes hisreceiver from the hook and entering into conversation with the operatorat central is notified by the operator that O wishes Ito talk to him.The operator then returns the hand 16, so that it rests upon the point 5and the point 5 which is in radial alinement therewith, thuselectrically connecting points 5 and 5 The subscriber 0'' having removedhis receiver from the hook, the lever 39 is in engagement with thecontacts 38 and 52 and carries the strip 4-7 out of contact with thepoints 48 and 49. At this time the transmitter 30 is in circuit with thewire H through the wire 37, contact 38, lever 39, and contact 52 andthat portion of the signal-wire H between the two subscribers stationsis cut out. The two subscribers are then in a talking-circuit whichincludes the wire I, points 1, 5, and 5, the contact F, and the wire Hand the ground. Supposing that the subscriber G wishes to talk to someone on the line 26 beyond the board ct, he calls up the central operatorin the manner hereinbefore described, using the signal-wire H, and theoperator moves the hand 16 to the point 1 and the hand 16 to thepoint 1. The point 1 connects the subscriber with the line 23 throughthe hand 16, and the hand 16' being on a dead-point no current can passfrom said hand 16', but passes onto the line 26 and through said line tothe distant instrument.

It will be noted that with this apparatus when any one subscriber isconversing with another subscriber no one can hear any portion of theconversation excepting the person with whom conversation is had and theoperator at central. Furthermore, when talking with central no othersubscribercan hear the conversation.

The apparatus at c is a duplicate of that at C, while the apparatus atc" is like that at C. If the subscriber at C wishes to talk with thesubscriber at 0, he operates his magneto and the current traverses thesignal-wire H, and the hand 16 being normally at one of thesignalcontacts the current passes through said hand to the wire 24 tothe operators instrument and he is rung up. The subscriber at C thentakes down his receiver and his transmitter is out into circuit withboth wires H and I, but the hand 16 being on a signal-contact, such asD, there can be no flow of current along the wire I, and conversation ishence held with the operator over the signal-wire H. The subscriber thentells central that he wishes to talk with the subscriber at c", and theoperator then sends a sufficient number of alternations of current overthe line 24 and through the magnet 20 and over the line 23 and throughthe magnet of the board a to cause the hand 16 to move to the contact 2and the hand 16 to move to the contact 2'. When the hand 16 movesfromthe contact D, the circuit of the signal-wire H is broken, and inasmuchas the contact 1 of the switchboard A is connected with the contact 2the current will pass from station 0 over the wire I to contact 1, tocontact 2 through the hand 16 and wire 23 to hand 16, and thence topoint 2', to point 2, to wire 7r, to the instrument at the subscribersstation 0''. When the subscriber at 0 begins conversation with centralor with any subscriber, as soon as the receiver is taken from the lever39 the latter is operated and moved from contacts 48 and 49 to out outthat portion of the wire H at the opposite side of subscriber G from theboard A, so that the subscriber at 0 cannot use the signal-wire, andhence cannot hear any portion of the conversation. Should the subscriberat O attempt to listen to the conversation between 0 and the centraloperator over the wire H, he would of course have to remove his receiverand the lever 39 would immediately be operated to cut C off from thewire H. In any event one subscriber cannot overhear the conversation ofanother subscriber that is not intended for him.

It will be noted that for sending alternate currents from the main linea simple form of lever O is employed, above and below which are arrangedpairs of contacts 0' and 0, respectively. The contacts 0 are connecteddirectly with the instrument 25 at central, while the contacts 0" areconnected directly to the main-wire line 24, leading to the subscribers.The contact 0" at the left is connected to the contact 0 at the right,and the contact 0' at the right is connected to the contact 0 at theleft. The lever O has its end portions insulated from each other andconnected with the corresponding terminals of the battery P. As thelever O is rocked it connects the battery reversely between theinstrument 25 and the wire 24.

It will be noted that the magnets 20 are in multiple between theinstrument 25 at central and the ground. The magnets are so wound thatthe resistances of the circuits of the magnets are substantially thesame, and they will therefore be operated simultaneously. At central isan ordinary telephone instrument, as illustrated, which is normallyconnected between the instrument 25 and the switchboards, so that when asubscriber calls up central the bell of the instrument at central willbe sounded and conversation may be had with central, so that directionsmay be given for connecting the subscriber with the proper othersubscriber. been notified of the subscriber wanted, he operates theswitch 75 so that his'telephone instrument is cut out of the circuit andthe lever 0 and its mechanism is cut into circuit and may be thenoperated to energize the magnet 20. and operate the hands 16 and 16; Itis of course understood that the hand or index of the instrument 25 islikewise pro- When central has v Vided with a mechanism including alever, an armature, and a magnet, so that all three indeXes or handswill travel synchronously.

The magnetos used for calling up central and for calling up thesubscribers are continuous-current magnetos, so that in calling up theescapement mechanisms of the switchboards are not eifectod, but are onlyeffected when alternating currents are transmitted as, for instance,when the lever O is operated at central. With the wiring shown if thesubscribers were provided with alternating magnetos they would whenoperated actuate the escapement mechanism and send the indexes over thedials.

What is claimed is 1. In a system of the class described the combinationwith a plurality of subscribers stations, a line-wire for eachsubscribers station, and a central operators station, of a switchboardcomprising a plurality of contacts for each subscribers station and withwhich said subscribers line-wire is connected, a signal-wire common toall of the subscribers instruments, a plurality of contacts on theswitchboard with which said signal-wire is connected, a return, meansfor connecting each subscribers line-wire in multiple with thesignal-wire between the switchboard and the return, and an operatorswire, said switchboard including a contact-arm with which the operatorswire is connected, said arm being adapted to contact with certain of thesignalwire contacts and certain of the subscriberswire contactsindividually, and to engage a signal-wire contact and a subscribers-Wirecontact simultaneously.

2. In a system of the class described the combination with a pluralityof subscribers stations, a line-wire for each subscribers station, and acentral operators station, of a switchboard comprising a plurality ofcontacts for each subscribers station and with which said subscribersline-wire is connected, a signal-wire, common to all of the subscribersinstruments, a plurality of contacts on the switchboard with which saidsignal-wire is connected, a return, means for connecting eachsubscribers line-wire in multiple with the signal-wire between theswitchboard and the return, an operators wire, said switchboardincluding a contact-arm with which the operators wire is connected, saidarm being adapted to contact with certain of the signalwire contacts andcertain of the subscriberswire contacts individually, and to engage asignal-wire contact and a subscribers-wire contact simultaneously, andmeans for cutting off the remote subscribers from connection with theswitchboard through the signal-line, when an instrument nearer to theswitchboard is operated.

3. A system of the class described comprising a plurality ofswitchboards each including a dial and a contact-hand adapted totraverse the dial, an operators instrument connected directly with allof the hands, a plurality of subscribers stations for each switchboard,a line-wire for each subscribers station, a plurality of contacts oneach switchboard for each subscribers stationand with which saidsubscribers line-wire is connected, a signal-wire common to all of thesubscribers instruments of each switchboard, a plurality ofsignal-contacts on each switchboard with which the signal-wire of thatboard is connected, a return, means for connecting each subscribers linein multiple with the corresponding signal-wire between the switchboardand the return, the arm of the switchboard being adapted to contact withcertain of the signal-wire contacts and certain of the subscribers-wirecontacts individually and to engage a signal-wire contact and asubscribers-wire contact simultaneously.

4. A system of the class described comprising a plurality ofswitchboards each includingadial and acontact-hand adapted to traversethe dial, an operators instrument connected directly with all of thehands, a plurality of subscribers stations for each switchboard, aline-wire for each subscribers station, a plurality of contacts on eachswitchboard for each subscribers station and with which said subscribersline-wire is connected, a signal-wire common to all of the subscribersinstruments of each switchboard, a plurality of signal-contacts on eachswitchboard with which the signal-wire of that board is connected, areturn, means for connecting each subscribers line in multiple with thecorresponding signal-wire between the switchboard and the return, thearm of the switchboard being adapted to contact with certain of thesignal-wire contacts and certain of the subscribers-wire contactsindividually and to engage a signal-wire contact and a subscribers-wirecontact simultaneously, and means for progressing the hands of theswitchboards simultaneously to engage corresponding contacts.

In testimony whereof I at'fix my signature in presence of two witnesses.

WAYNE O. WRIGHT.

Witnesses:

GEo. W. CHANDLER, ALFRED B. DENT.

